Control for engine starting means



SPt 2, 1958 J. H. DAvlDs 2,849,857

CONTROL FOR ENGINE STARTING MEANS Filed Oct. 6, 1954 2 Sheets-Sheet 1Q-T M a Sept 2, 1958 J. H. DAvlDs 2,849,857

CONTROL FOR ENGINE STARTIN. MEANS Filed oct. e 1954 I CONTRL FUR ENGENESTARTING MEANS John H. Davids, Beloit, Wis., assignor to Fairbanks,Morse & Co., Chicago, Ell., a corporation of Illinois Application ctober6, 1954, Serial No. 460,678

s claims. (c1. sti- 16) This invention relates to improvements in thecontrol of starting provisions 'for internal combustion engines, andmore particularly to an improved method of,- and control means for,controlling the operation of the engine starting means such as toterminate starting operation thereof automatically in response tostarting acceleration of the engine to and above a given or selectedengine speed.

Engine starting provisions of heretofore known and prevailing types, ascompressed air starters and the like, fumsually include either amanually operated control or an cutomatic control mechanically operatedgenerally in accordance with engine speed, as effected through theengine ,peed controlling governor or other mechanical device atctuatedin accordance with engine speed. Such controls gjenerally embodygearing, linkage mechanisms or other ngiechanical connections from themanual lever, engine governor or other speed operated device, whichconnections present certain disadvantages in respect to manu-facturiugand maintenance costs, and the overall complexity of the controlrequipment.

The principal objective of the present invention, therefore, is toafford in connection with engine starting means, a greatly simplifiedyet highly effective control provision for interrupting'operation of thestarting means automatically upon engine starting acceleration to andabove a given speed, wherein the control provision while operativelydependent upon engine speed, does not embody or utilize gearing,linkages or other mechanical connections of the character abovementioned.

More particularly, the present invention is `concerned with internalcombustion engines having iiuid pressure systems, as pressurelubricating oil and/r cooling water circulating systems, wherein thepressure of the fluid is proportional Vto engine speed. Given such anengine including suitable starting 'means therefor, it is an objectofthe invention to aiiord simplified control of the starting means in amanner to effect termination of engine starting operation ofthe startingmeans in response to the pressure 'obtaining'in a nid pressure system ofthe engine 'upon engine-starting acceleration to a predetermined orselected engine speed. In one form of the invention as herein disclosedin connection with an engine of the character indicated, having an airpressure starting system, there is provided a` starting air supplycontrol valve rnormally biased to an open condition permitting startingair delivery to the engine, wherein the valve embodies pressure-actuatedmeans in connection to the iiuid pressure system 'of `the engine,operative to close the valve and hence Vterminate starting vair supplyto the engine, upony and in response to pressure rise in the engineiiuidl pressure `system to an extent determined by engine startingYacceleration to a selected speed, as to a speed belownormal engineoperating speed. The present invention is applicable also, to othertypesof engine starting means, as electriclmotor starters and the like, anexample of which is illustrated herein.

nited tates atent O rice The foregoing as well as other objects andadvantages of the invention will appear from the following descriptionconsidered in connection with the accompanying drawing, wherein:

Fig. lillustrates diagrammatically, an internal combustion engineincluding an air` start system and a cooling iiuid circulating system(shown only in part), together with a starting air supply control valveshown in vertical section, the valve including a fluid pressureoperating means in pressure-responsive connection to the engine coolingiiuid system;

Fig. 2 illustrates diagrammatically, application of the invention tocontrol of an electric motor and clutch type engine starter means, and

Fig. 3 shows diagrammatically, an engine having a pressure lubricatingfluid system with which the present invention may be employed.

Referring iirst to the embodiment according to Fig. l, an internalcombustion engine is illustrated diagrammatically and in part only, asincluding cylinder assemblies 10, and pistons 11 operatively associatedwith the crankshaft 12 through connecting rods 14. The engine is ofjacketed, water-cooled type providing cylinder jacket spaces 15 in acooling water circulating system including water delivery and returnheaders 16 and 18 respectively. Branch connections 19 from deliveryheader 16, supply cooling water to the cylinder jacket spaces 15, whileconnections 20 connect the cylinder jacket spaces to the return header18, the latter extending to a suitable cooler 22 from which the cooledWater is returned to the source indicated by the tank 23. From thesource such as tank 23, water is delivered to supply header 16 by asuitable pump, as a centrifugal pump 24, which is driven from the enginecrankshaft 12. With the pump engine driven as indicated, the speed ofthe pump will yvary correspondingly with variations in engine speed, andthus the pumpestablished pressure ofthe cooling fluid or Watercirculating in the engine` jacket system, will vary with and be invproportion to engine speed. Hence the water pressure in the systemdirectly reflects engine speed, and this pressure as it increases withengine acceleration in starting, is utilized as the controlling mediumin effecting termination of operaton of engine starting means.

In the embodiment of the present invention according to Fig. ltheyengine is provided with a compressed air starting system which in theexample shown, includes an air supply conduit'26 extending from asuitable source of compressed air (not shown) to an air distributorgenerally indicated at 27. The distributor is operated from the` enginecrankshaft 12 for proper timing of air delivery to the several enginecylinders, air delivery being effected .through conduits 28 to airvalves 30 in the cylinder heads 31, as in the usual or well known airstart systems. A

. manuallycontrolled or otherwise suitably operated main shut-olf valve32 may be included in conduit 26. Interposed in the supply conduit 26 inthe portion thereof between the shut-off valve 32 and the distributor,is a control valve device 34 shown in vertical sectional detail,providing a. starting air cut-off control in the present exemplaryembodiment of the invention.

As appears in Fig. 1, the valve device 34 comprises a valve body 35having a central vertical bore 36 in which slides `a pistontype valveelement 38 in controlling relation toa compressedl air inlet port 39 atthe inner end of inlet passage 40. Connected to inlet passage 40 is theend portion 42 of that part of supply conduit 26 leading from thecompressed air source (not shown). The end 43 of'that part of conduit 26between the valve and the distributor Z7, is connected to the valveoutlet passage 4 4, the latter having the outlet port 46 associated withthe piston valve element 38 as shown.

The valve body has an open bottom recess 47 which in valve assembly, isclosed by `a cup-shape cover or closure member 48 having an internalboss or land 50 in alignment with the valve bore 3,6. The cover boss orland 5 0 pfrovides a stop for abutment byra projection at the lower endof the piston valve 38, to limit valve movement in thc downward orvalve-opening direction. Projection 51 may be provided as a part of amovable fluid motor element secured to the valve, as hereinafterdescribed. The piston valve is biased toward the stop and to thefull-open position shown, by a suitable compression spring 52 bearingagainst the upper end 54 o'f the piston valve, as through a washer 53.Spring 52 eXtendsupwar-dly in a vertically elongate cap member 55removably attached to the valve body, and engages at its upper end aVdisc or washer 56 carried by. a spring. adjusting'element- 'orf screw58 threaded through the top wall 59y of cap 55 and provided with a locknut 60. Thus by. threading the screwl in one or the4 other. direction,the biasingL force of the'spr-ing on the` piston valve may. becorrespondinglydetermined, as for a particular purpose presently to beindicated. l

Marginally secured or clamped between the cover 48 and the. lOWtI` Gndf` the. valve. bodyl is a exible member or diaphragm 6,2 whichcooperates withthe cupshape cover to` form a fluid pressure chamber 63.The diaphragm in its central area, is operatively associated with thelower` and. O f; the piston valve, as with a head or flans@ member 64preferably provided as an integral part of the piston valve. Mo ieoverand as hereinaboye indicated, diaphragm 62 is bossed or enlargedSubstantially at its center, t0. provide. the Sten projection 5.1engageable with the casing stop 5 0, rI 'he valye body recess 47accommof dates the Pisten. tiene@ 64111. uuward displacements thereof influid pressure actuation of the. diaphragm. Connectins the iluid.pressure Chamber 6 3. with the. engine cooling water system is amconduit 66, this Conduit in the present example, being shown asextending. to connection at 67 with the Coelinswater Supply header. 16Qf the engine. Hou/even the conduit. 66u may be connected to any otherSuitable Orconvenient point in. thev cooling water pressure circulationsystem embodied in the, engine assembly, as for instance,y te` any1 oneofthe cylinder jacket SPHQSS Thus.. tllepr'essure chamber 63. anddiaphragm 62 in iluid. pressure association.- with the.r ensine CoolingWater system emv-isles a lluidpressnre actua-` tor or tluid Servo-motorfor; the piston valve element 38-V In the operation ofthe control valve.dev e 34, the latter is now described, when the enginedA -s itopped orat rest, the cooling water in the, engine eoolingI system will be under10W. or pressure insuiient to cause displacement 0f. the diaphragm. 6.2trom the position. shown in Fig). l, which is that corresponding tofull-open position 0f the piston, valve `iii\Yl.1= 1eii1 the abutrnentliS against Stop 50,7 as. direte@ under the bias of valve Spring 521 lliSuch PQSitiQn. ofthe. piston valve. communication is established bytherlatter between the valve inlet and outlet ports 3 9, and 46,respectively, s o that upon Opening Ofmain valve,3,2mcofiipre,S.S.s=,fl;air,r Will'` 116W from the source through conduit26 and the Valve 3,4; to the distributor Asis usual in 's ta-rtsystenas,thedistributor nennits` compressed air; deliysl'v t'Q at: least one ofthe engine cylinders at the begi ing of engine starting, and thereafteras the engine accelerat y it determines air delivery to the cylinders.in3 a` given sequence, usually inj accordance with t l cylinder-.firingorder of. the engine.; Now, a een eunder jesstarting acceleration, withcranlshah. drive of.V the cooling water pump 24, at correspondinglyincreasing speed, the pressure of the cooling water. circul ingin the engine jacket system, risespropo nately. When, during such startingacceleration ofthe engine, the cooling water pressure rises to. a pointsuch that thepressurgein the valve servo-motor chamberg. excee s ftheopposingpressure of the valve biasing 5 2 \the.Se IV.0Il1J9CQTdla phragm62 will undergo fluidZ pressure displacement to r4 l move the pistonvalve 38 upwardly toward and to a position closing the air inlet port39. With valve closure of port 39, compressed air delivery through thevalve to the distributor 27 is then cut-off or terminated.` Thereafterand as the engine assumes normal running conditions, the cooling waterpressure then obtaining in consequence of the operating speeds of theengine, adequately exceeds the biasing force of spring 52 such as toassure and maintain valve closure throughout engine operation. While notimportant to the present invention and hence not shown, upon closure ofthe control valve 34 air may be vented from the cylinder conduits 28,and if desired also, from the portion of conduit 26 between valve 34 andthe distributor 27, in any suitable manner. Upon stoppage or shut-downof the engine, and assuming that the main valve 32 is actuated to closedposition coincidentally therewith, the cooling water pressure will dropto a low value, so that the pressure in chamber 63 will beeome wellbelow the opposing pressure of the control valve spring 5 2, whereupon,the spring will move the piston valve to its full-open position (Fig.l), thereby conditioning tbe valve for operation in the next orsucceeding engine starting period.

It is to be noted here that the valve biasing spring 52 is of selectedcapacity in relation to the full pressure range of the cooling watersystem of a given engine,` so that under adjustment of the spring toimpose a minimum biasing pressure, the valve will open against low orminimum fluid pressure of the cooling system in engine shutdown, andjfurther, so that the spring may be adjusted to a condition in which itwill be overcome only by that fluid pressure obtaining when the enginespeed in starting acceleration, attains at most a predetermined speedwhich may be that speed at which the engine converts from air start torunning on fuel. of the spring then will determine valve closure at acoirespondingly lesser engine starting speed.

As shown in Fig. l, included in the control valve ,fievice 34 is anindicator to provide visual indication of/lrhe open and closedconditions ofthe valve. Conveniently, the indicator is in the form of arod which may be carried by the spring washer V53 on the upper end ofthe piston valve, the rod extending upwardly in cap member 55 to andthrough an axial passage or bore 71 in the spring adjusting screw 58, to`exposure of its upperend 72 at the screw head 74. In the full-opencondition of the valve, the rod 70 will be retracted relative to thescrew so that its exposed end 72 then may be approximatelyy hush withthe top of the screw head 74, depending upon the spring adjustingposition of the screw, while in the closed condition ofthe valve, therod will project above the screw head 74.

In the embodiment of the invention according to Fig. 2, shown inessentially diagrammatic manner, the engine 80 includes a cooling watercirculating system indicated in part at 81, in which the pressure of thecooling water is in accordance with engine speed, as in the embodimentof Fig. 1 for example. The starting provision for the engine maycomprise an electric motor 82 having its output shaft 84 connected tothe engine crankshaft 85 through a clutch device 86 of any suitableform. The clutch is here indicated as including a clutch element 88movable to and from clutching engagement with a com-l plementary clutchelement 89, with movement thereof under control of a lever 90 pivotallysupported at 92 intermediate its length. The lever is biased by asuitable spring 93 in the direction to locate clutch element 88 out ofengagement with clutch element 89, while lever actuation to cause clutchengagement is effected by the movable armature of a s-olenoid motordevice generally indicated at 94. -The solenoid motor has its movablearmature 96 connected by a link or rod 97 to the clutch lever at 98, andits energizing winding 100 connected to power supply lines L1 and L2including in the line L2 a switch Any intermediate adjustments;

of the engine cooling `fluid circulating system.

101. Starting mot-or 82 is energized from supply lines L1 and L2 overleads 102 and 104, the lead 104 being connected to line L2 at a point105 between the switch 101 and the solenoid winding 100. Thus, when theswitch 101 is closed the solenoid motor 94 is energized to draw-in itsarmature 96 and actuate clutch lever 90 to engage clutch element 88 withelement 89, and simultaneously the starting motor 82 is operated tocause through the then engaged clutch device, starting of the engine 80.Opening of switch 101 effects de-energization of both the starting motorand the solenoid motor, and hence termination of starting motor drive ofthe engine crankshaft, with disengagement of the clutch under the biasof spring 93.

Control of the switch 101 is effected through a uid pressure servo-motor106 having a diaphragm or movable piston element 108 in a uid pressurechamber 109, the chamber being connected by a conduit 110 to a suitablepoint in the engine cooling water circulating system 81. Switch 101 hasan operating rod 112 eX- tending to connectionwith the servo-motorpiston or diaphragm 108, and includes a suitable bias, as thecompression spring element 113, acting on the diaphragm and rod in thedirection to effect switch closure and location of the diaphragm in aninitial position. The switch-closing effect of the spring 113 isadjustable, as through the adjusting screw 114 in support of one end ofthe spring.

Infengine starting, when the main supply line switch ,116 is closed andsince switch 101 then is closed under Aits bias spring 113, the solenoidmotor will be energized ifo engage the clutch, while the starting motorsimultaieously energized, operates through the clutch to turn v heengine crankshaft. Now as the engine is accelerated i t starting, thecooling fluid pressure rises in the engine Coioling system 81 andconsequently in the servo-motor chamber 109. When the pressure inchamber 109 eX- cee'dls the opposing bias of spring 113, the piston ordiaphragm 108 responds by fluid-'pressure displacement in the directionto open the switch 101, thereby terminating engine starting 4drive bythe motor y82 as hereinabove described. Thereafter and throughoutrunning operation of the yiengine, the spring 93 retains the clutchelement 83 Vdisengaged from the clutch element V89 on the enginecranksliaft, since the switch 101 then is maintained in open conditionby the fluid pressure servo-motor which remains infp'ressure operatedcondition during normal operation It is to be noted that by adjustmentof the switch bias spring 113 through the adjusting screw 114, pressureoperation of the servo-motor to open the switch 101 and hence terminateoperation of the engine starting provision in the manner described, maybe regulated to occur at a selected speed in engine startingacceleration. IIn respect to a given engine to which the starting systemis applied, such adjustment normally will be made so that theservo-motor will act to open switch 101 and sto-p the starting drivewhen the engine starting speed is at or slightly above the speed pointat which the engine converts to fuel operation.

Upon stoppage or shut-down of the engine, the pressure of the uid in theengine cooling system drops to a low or minimum value, whereupon spring113 closes switch 101 to condition the energizing circuit for operationof the starting motor 82 and operation of the solenoid motor 94 toengage the clutch 86. The engine then may be again started by closure ofthe main supply switch 116.

While in the embodiments of Figs. 1 and 2, termination of operation ofthe engine starting provision 1s controlled from the engine coolingwater circulating system in the manner now fully described, suchcontrol4 may be effected from the engine lubricating system in enginesproviding pressure feed of lubricating fluid wherein the oil pressurevaries proportionately with engine speed. For example, as showndiagrammatically by Fig. 3, an engine has a suitable oil pump 121illustrated as of a gear type, driven from the engine crankshaftrepresented by the broken line 122. The pump may take oil from theengine crankcase sump 124 and deliver under pressure to a pressuresupply manifold 125 from-which branch conduits, as 126, lead to pointsof pressure lubrication in the engine. Now, with the air start system ofFig. l applied to this engine, the pressure uid conduit 66 leading tothe fluid pressure servo-motor of the control valve 34 may be connectedto the oil pressure system at any suitable point therein, as at 128 inthe manifold 125. Similarly in the instance of application of theelectric motor and clutch starting system of Fig. 2 to the engine 120,the servo-motor conduit 110 may be connected to the same point 128 ofthe pressure oil manifold 125. It will be understood that because of theusually higher pressures in the lubricating system as compared to thepressures obtaining in the conventional cooling water pressurecirculating system, where the air start system of Fig. l is used, thevalveopening and servo-motor biasing spring 52 in the valve device 34will be selected as to capacity, such as to accommodate the higher oilpressures. Likewise, in the instance of use of the motor starting system0f Fig. 2, the switch-closing and servo-motor biasing spring 113 will besimilarly selected as to capacity.

Having now illustrated and described several embodiments of the presentinvention, it is to be understood that modiiications of the embodimentsshown, as well as other embodiments, may be made within the spirit andscope of the invention as hereinafter claimed.

What is claimed is:

l. In combination with an internal combustion engine having a fluidpressure system in which the pressure of the fluid therein isproportional to engine speed, iiuid pressure starting means for theengine including a control valve normally biased to an open condition,and a liuid pressure actuated servo-motor in constant open'communicationwith said uid pressure system, elfective for closing said control valvein response to fluid pressure obtaining in said fluid pressure systemwhen the engine attains and exceeds a predetermined engine speed.

2. In combinaiton with an internal combustion engine having a fluidpressure system wherein the pressure of the fluid therein isproportional to engine speed, fluid pressure starting means for theengine including a control valve, uid pressure actuated valve closingmeans in constant open communication with said fluid pressure system,and valve opening means effective to open and retain said control valveopen when the fluid pressure acting on said valve closing means is in aninitial pressure range corresponding to the engine speed range from zerospeed to a predetermined engine speed less than the normal running speedof the engine.

3. In an internal combustion engine having av cooling iluid jacketsystem, engine driven pump means for circulating cooling fluid in thejacket system at a pressure increasing with increasing engine speed, anda compressed air starting system, the combination therewith of a controlvalve in the compressed air starting system, said control valveproviding a movable valve element and yieldable means biasing the valveelement to a valve open position, and fluid motor means connected to theengine jacket system andl operatively related to said valve element,said iluid motor means operating in response to lluid pressure obtainingin the engine jacket System when the engine attains a predeterminedengine speed, to move said valve element to a valve closed position.

4. Inan internal combustion engine having a cooling tiuid jacket system,engine driven pump means for circulating cooling uid in the jacketsystem at pressures corresponding with engine speeds, and a compressedair starting system, the combination therewith of a control valve in thecompressed air starting system, said control assainir'k valve providinga movable valve element, uid motor` means connected to the engine jacketsystem and to said valve element, operable by cooling iluid pressure formoving said valve element to a valve closed position, and yieldablemeans acting on said valve element in opposition to, said motor means,for lmoving the valve element to4 a valve open position, said yieldablemeans yielding to. permit valve closing movement of the valve element bysaid fluid motor means only when the jacket uid pressure attains andexceeds a pressure value corresponding to a predetermined engine speed.

5. In an internal combustion engine having a cooling fluid jacketsystem,engine driven pump. means for cir-V culating cooling uid in the jacketSystem at a pressure increasing with increase in engine speed, and anair start system including a compressed air supply line, the cembinationtherewith of a control valve in said air supply line, the control valveproviding a movable valve element, fluid motor means actuated by fluidpressure in the engine jacket system and operable on said valve elementfor moving the latter to a valve closed position, yieldable spring meansbiasing said valve element to a valve open position and imposing throughthe valve element, a force on said uid motor opposingy uid pres-References Cited in the` file of this patent 4 UNITED STATES PATENTS1,277,541 Brownback Sept. 3, 1918 1,632,023 Danielsson June 14, 19271,647,231 Junkers Nov.Y 1, 1927 1,999,199 McGrath Aprj30, 1935 2,013,238Furgason Sept. 3, 1935 2,040,333 Rathbun MayV 12, 1936 2,366,144Griswold Dec. 26, 1944 2,633,868 Berhoudar Apr. 7,1953

OTHER REFERENCES Powe-m, issue of March 1945, page 102 (184).

